Cameras, such as surveillance cameras, for outdoor use need to be protected, e.g., against dust and rain. Sometimes it is also necessary to protect the cameras against vandalism, outdoors as well as indoors.
One common approach to solve this is to install a camera designed for indoor use inside an outdoor housing. Examples of this approach are, e.g., shown in US 2015/0256747 and US 2009/0115890. Such an approach is also applied in the AXIS T93F10 Outdoor Housing. In the latter example there is an optional accessory; a bracket can be purchased if the fixed camera needs to be installed in the so-called corridor format, allowing the housing to remain in the same orientation.
Some cameras are designed to be able to be used with different lenses or lens assemblies adapted for different viewing distances. With different choices of lens, the same camera may be used for anything from close-up surveillance of a door nearby the camera to long-distance surveillance of traffic with the camera positioned on a mast or large traffic sign.
Typically, it is desirable to install the camera inside the outdoor housing with the front end of the lens as close to the window of the outdoor housing as possible to minimize reflections. However, in order to meet requirements concerning protection provided by enclosures for electrical equipment against external mechanical impacts, e.g., protection against vandalism, it is often necessary to position the camera in the housing such that there is a specific minimum distance between the window of the housing and the lens, such that an impact on the window does not damage the lens or the camera.
One problem often associated with this design is that the outdoor housings become bulky.
Another problem associated with this design is that in warm climates the outdoor housings often need to be provided with a fan to provide an air circulation inside the outdoor housing to ensure sufficient cooling of the camera.
The cooling problem has been addressed, e.g., in US 2002/0140848 A1, which discloses the provision of a chamber for a surveillance camera that is designed to be mounted inside a larger camera housing. The internal chamber is sealed and provides a controlled internal environment for the sensitive camera optics and internal electronics. However, with this design there arises a need for sealed feed-through openings through the external housing, both to allow the electrical connectors of the internal camera to extend outside the housing and to provide conduits for adding and removing gases from the internal chamber. This is a complex design which would become even more complex if it were to be designed to accommodate different choices of lens for the camera inside the internal chamber.
The cooling problem has also been addressed in U.S. Pat. No. 7,362,372, which discloses a video surveillance camera comprising a housing with two chambers separated by a thermal barrier. This is also a complex design which would become even more complex if it were to be designed to accommodate different choices of lens for the camera inside the internal chamber.
It is also known to provide housings where one part of the housing moves in translation or rotation relative to another part of the housing. Such concepts are, e.g., shown in U.S. Pat. No. 5,563,659.
All in all, there exists a market need to provide an improved camera concept which may be used for outdoor placement, which addresses the cooling problem, which allows for use of different lenses and which may be used to address different protection classifications.